Impact of Implementing Nasal High Flow Therapy on Body Growth in Preterm Infants

Introduction: The objective of this study was to determine the impact of nasal high flow (nHF) implementation on lung growth at 6 months corrected age (CA) in preterm infants. Methods: This single-center retrospective cohort study included preterm infants born 30 weeks' gestation and surviving to 6 months CA at the neonatal intensive care unit of the Amsterdam University Medical Centers. In the nCPAP cohort (2009-2012), continuous distending pressure (CDP) was applied solely with nasal continuous positive airway pressure support. In the nHF cohort (2015-2018), nCPAP was used and followed by nHF therapy to deliver CDP. Bodyweight and length at 6 months CA were used as a proxy for lung growth. We also assessed the impact on respiratory management and neonatal morbidity. Multivariate analysis was performed after multiple imputation, using a linear regression adjusting for confounding variables. Results: Of the 598 eligible infants, 313 infants were included in the nCPAP cohort and 285 infants in the nHF cohort. The analyses showed no differences between the nCPAP and nHF cohort in body weight (7.29 vs. 7.31 kilogram, 95% CI -0.14 to 0.20, 0.71) and length (66.6 vs. 66.8 centimeters, 95% CI -0.30 to 0.81, 0.26) at 6 months CA. No differences in moderate/severe bronchopulmonary dysplasia (BPD) were reported, but nHF implementation was associated with longer CDP duration, a trend toward more days on supplemental oxygen, and a shift from moderate to severe BPD. Conclusions: Implementation of nHF did not impact body growth, which is associated with lung growth, at 6 months CA in preterm infants born 30 weeks.